What is another name for relative permittivity?
Dielectric strength
Electric intensity
Potential gradient
Dielectric constant
Correct Answer :
D. Dielectric constant
Related Questions
Which of the following materials has the least hysteresis loop area?
soft iron
silicon steel
hard steel
wrought iron
How is mutual inductance between two coils decreased?
By using a common core
By moving the coils closer
By moving the coils apart
By increasing the number of turns of either coil
A magnetic field is
The current flow through space around a permanent magnet
The force set up when current flows through a conductor
The force that drives current through a resistor
The force between the plates of a charged capacitor
Flux linkages equals
Flux times area of core
Flux times number of turns times area of core
Flux times number of turns times length of core
Flux times number of turns
The dielectric constant of most materials lies between
1 and 10
10 and 20
20 and 50
50 and 100
When a current carrying conductor is placed in a magnetic fielda the maximum force will act on the conductor when the conductor is at an angle of _______ to the magnetic field.
45o
60o
30o
90o
A t/m is a unit of
Mmf
Emf
Reluctance
Magnetizing force
Ohm's law can be used only to a _____ circuit or component.
Unilateral
Exponential
Trivalent
Linear
Electric potential is a _______ quantity.
scalar
phasor
vector
variable
A magnetizing force of 1000 AT/m will produce a flux density of __________ i
1.257 mWb/m^2
0.63 Wb/m^2
1.257 Wb/m^2
0.63 mWb/m^2
The force between two charges placed a given distance apart ______ as the relative permittivity of the medium is increased.
increases
decreases
remains unchanged
becomes infinite
An atom or a group of atoms that carries a net electric charge.
Positive ion
Negative ion
Ion
Electron
The temperature coefficient of resistance of conductors is
positive
zero
negative
infinite
Calculate the flux density that will be produced by the field intensity of 2000 a. t/m for a permeability of 126 x 10^-6 T/A.t/m
0.252 G
0.252 x 10^-2 T
0.252 T
0.252 x 10^-2 G
One coulomb of charge consists of ________ electrons.
624× 10^16
62.4 × 10^16
6.24 × 10^16
0.624 × 10^16
Defined as the ratio of the volume occupied by the atoms or ions in a unit cell divided by the volume of the unit cell and is used to measure the compactness of a crystal.
Atomic packing factor (APF)
Ionic Packing Ratio (IPR)
Atomic compacting factor (ACF)
Ionic compacting ratio (ICR)
Electronic current in a wire is the flow of ____________ electrons.
free
valence
bound
loose
What is the diameter of an atom?
About 10^-10 m
About 10^-10 cm
About 10^-10 mm
About 10^-10 �m
What is the unit of magnetomotive force?
Volt
Tesla
Ampere- turn
Weber
The unit of flux density is
Wb/m
Tesla
At/m
N/Wb
Under ordinary conditionsa a body is considered
positively charged
neutral
negatively charged
stable
A theorem which states that an electric current flowing in a circuit produces a magnetic field at external points equivalent to that due to a magnetic shell whose bounding edge is the conductor and whose strength of the current.
Joule's law
Faraday's law
Volta's theorem
Ampere's theorem
The quantity of magnetism retained by a magnetic material after withdrawal of the magnetizing force is called
Leftover magnetism
Hysteresis
Residual magnetism
Coercivity
The hot resistance of an incandescent lamp is about _______ its cold resistance.
10 times
100 times
5 times
50 times
Electric field intensity is a ________.
scalar
phasor
vector
variable
When the current flowsa the magnetic field ��. conductor is in what direction?
The same as the current direction
Opposite the current direction
Omnidirectional
In the direction determined by the left hand rule
The uncharged particles which have no effect on its atomic charge.
Nucleons
Electrons
Protons
Neutrons
It is the reciprocal of reluctance and implies the case of readiness with which magnetic flux is developed.
R esistance
Conductance
Permeance
I nductance
The force between two magnetic poles is _______ their pole strengths.
directly proportional to
the sum of
inversely proportional to
the product of
The property of a material which opposes the creation of magnetic flux in it
Resistance
Reluctance
Permeance
Conductance